U.S. patent number 8,497,845 [Application Number 13/049,914] was granted by the patent office on 2013-07-30 for sensing structure of touch panel.
This patent grant is currently assigned to Chunghwa Picture Tubes, Ltd.. The grantee listed for this patent is Bo-Han Chu, Wen-Che Wang. Invention is credited to Bo-Han Chu, Wen-Che Wang.
United States Patent |
8,497,845 |
Wang , et al. |
July 30, 2013 |
Sensing structure of touch panel
Abstract
A sensing structure of a touch panel includes a substrate, a
plurality of sensing electrodes, a plurality of electro static
discharge (ESD) protection electrodes, a plurality of first
bridges, and a passivation layer. The sensing electrodes, the ESD
protection electrodes, and the first bridges are disposed on the
substrate. The passivation layer is disposed between the sensing
electrode and the first bridge, and disposed between the ESD
protection electrode and the first bridge. The passivation layer
has a plurality of contact holes, and at least one sensing
electrode is electrically connected to the ESD protection electrode
via the contact hole and the first bridge.
Inventors: |
Wang; Wen-Che (New Taipei,
TW), Chu; Bo-Han (New Taipei, TW) |
Applicant: |
Name |
City |
State |
Country |
Type |
Wang; Wen-Che
Chu; Bo-Han |
New Taipei
New Taipei |
N/A
N/A |
TW
TW |
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|
Assignee: |
Chunghwa Picture Tubes, Ltd.
(Bade, Taoyuan, TW)
|
Family
ID: |
46490400 |
Appl.
No.: |
13/049,914 |
Filed: |
March 17, 2011 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20120182230 A1 |
Jul 19, 2012 |
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Foreign Application Priority Data
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Jan 14, 2011 [TW] |
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100101346 A |
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Current U.S.
Class: |
345/173; 345/174;
178/18.01 |
Current CPC
Class: |
G06F
3/0443 (20190501); G06F 3/0446 (20190501); G06F
2203/04111 (20130101) |
Current International
Class: |
G06F
3/041 (20060101) |
Field of
Search: |
;345/173-179
;178/18.01-18.06 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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2010218542 |
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Sep 2010 |
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JP |
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2011165159 |
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Aug 2011 |
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JP |
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2011192251 |
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Sep 2011 |
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JP |
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2011528147 |
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Nov 2011 |
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JP |
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M375934 |
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Mar 2010 |
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TW |
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Primary Examiner: Mengistu; Amare
Assistant Examiner: Patel; Premal
Attorney, Agent or Firm: Hsu; Winston Margo; Scott
Claims
What is claimed is:
1. A sensing structure of a touch panel, comprising: a substrate; a
plurality of sensing electrodes, disposed on the substrate; a
plurality of electro static discharge (ESD) protection electrodes,
disposed on the substrate; a plurality of first bridges, disposed
on the substrate; a passivation layer, disposed between the sensing
electrodes and the first bridges, and disposed between the ESD
protection electrodes and the first bridges, wherein the
passivation layer has a plurality of contact holes, and at least
one of the sensing electrodes is electrically connected with the
ESD protection electrodes via the contact holes and the first
bridges; and a plurality of second bridges, disposed on the
substrate, wherein at least one of the sensing electrodes is
electrically connected with the adjacent sensing electrodes via the
contact holes and the second bridges, and each of the first bridges
comprises two contact parts and one connection part, wherein a
width of the connection part is wider than or equal to a width of
the second bridge, and a width of the contact part is wider than
the width of the connection part.
2. The sensing structure of the touch panel of claim 1, wherein the
passivation layer is disposed on the first bridges, and the sensing
electrodes and the ESD protection electrodes are disposed on the
passivation layer.
3. The sensing structure of the touch panel of claim 1, wherein the
passivation layer is disposed on the sensing electrodes and the ESD
protection electrodes, and the first bridges are disposed on the
passivation layer.
4. The sensing structure of the touch panel of claim 1, wherein at
least one of the ESD protection electrodes is disposed between the
sensing electrodes adjacent to each other.
5. The sensing structure of the touch panel of claim 1, wherein at
least one of the sensing electrodes comprises a hollow region, and
at least one of the ESD protection electrodes is disposed in the
hollow region of the sensing electrode.
6. The sensing structure of the touch panel of claim 1, wherein the
substrate of the sensing structure of the touch panel is a
substrate of a display panel.
7. The sensing structure of the touch panel of claim 6, wherein the
ESD protection electrodes, the sensing electrodes, the first
bridges and the passivation layer are disposed on an outer surface
of the substrate of the display panel.
8. The sensing structure of the touch panel of claim 6, wherein the
ESD protection electrodes, the sensing electrodes, the first
bridges and the passivation layer are disposed on an inner surface
of the substrate of the display panel.
9. The sensing structure of the touch panel of claim 1, wherein the
substrate of the sensing structure of the touch panel is disposed
on a substrate of a display panel.
10. The sensing structure of the touch panel of claim 1, wherein
the sensing electrodes and the ESD protection electrodes are formed
by an identical conductive material layer.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a sensing structure of a touch
panel, and more particularly, to a sensing structure of a touch
panel capable of electro static discharge protection.
2. Description of the Prior Art
The touch panel has been widely used in the input interfaces of the
instruments for its properties such as the diversification for
design and the interaction between machines and humans. In recent
years, more consumer electronics, such as mobile phones, GPS
navigator systems, tablet computers and laptop computers, are
employed with touch display panels.
There are many diverse technologies of touch panel, and the
resistance touch technology, the capacitive touch technology and
the optical touch technology are the main touch technologies. The
capacitive touch technology has become the mainstream touch
technology for the high-end and the mid-end consumer electronics,
because the capacitive touch panel has advantages such as high
precision, multi-touch, better endurance, and higher touch
resolution.
A capacitive touch panel is disclosed in T.W. Pat. No. M375,934
issued Mar. 11, 2010 to Wu. The capacitive touch panel includes a
plurality of first electrode sets and a plurality of second
electrode sets disposed vertically. Each of the first electrode
sets includes a plurality of first transparent electrodes and a
plurality of conducting lines electrically connected with the two
adjacent first transparent electrodes. Each of the second
electrodes sets includes a plurality of second transparent
electrodes, and a connecting point is disposed between a conducting
line and the two adjacent second transparent electrodes. The
connecting point includes a transparent insulating layer covering
each of the conducting lines, an ESD protection line connected to
the two adjacent second transparent electrodes over the transparent
insulating layer, and a metal line disposed on the surface of the
ESD protection line, wherein the two ends of the metal line are
disconnected with the two adjacent second transparent electrodes.
Because the electrical signals of the second electrode set are
transmitted via the ESD protection lines and the metal lines, the
ESD protection effect of the metal lines is enhanced.
Please refer to FIG. 1. FIG. 1 is a schematic diagram illustrating
a top view of the conventional sensing structure of the touch
panel. As shown in FIG. 1, the conventional sensing structure of
the touch panel includes a plurality of first sensing electrodes
14C, a plurality of second sensing electrodes 14D, and a plurality
of bridges 11. The first sensing electrodes 14C are disposed
interlacedly with the second sensing electrodes 14D. Each of the
second sensing electrodes 14D is electrically connected with the
adjacent second sensing electrodes 14D in a horizontal direction X.
In a vertical direction Y, each of the first sensing electrodes 14C
is electrically connected with the adjacent first sensing
electrodes 14D via the bridge 11. The bridges 11 and the first
sensing electrodes 14C/second sensing electrodes 14D are disposed
on different layers. In the capacitive touch technology, the
sensing electrodes are used to detect the variations of electrical
capacitances around the touch points, and the feedback signals are
transmitted via the connecting lines along the direction X and the
direction Y for positioning the touch points. When operating the
capacitive touch panel, electro static charges may be generated and
result in an electro static discharge (ESD) phenomenon in the touch
panel. Because the resistance inside the touch panel is close to
zero, a heavy current may be generated by the ESD in the touch
panel. The heavy current may pass through the bridges 11, which
have relatively higher resistance. An electric energy may be
released at the bridge 11 and burn down the bridges 11. The
reliability of the touch panel is affected seriously by the ESD
damages, and therefore, a solution for ESD damages is eagerly
demanded.
SUMMARY OF THE INVENTION
It is one of the objectives of the present invention to provide a
sensing structure of a touch panel for improving the reliability
problem caused by the ESD damages in the touch panel.
To achieve the purpose described above, the present invention
provides a sensing structure of a touch panel. The sensing
structure of the touch panel includes a substrate, a plurality of
sensing electrodes, a plurality of ESD protection electrodes, a
plurality of first bridges, and a passivation layer. The sensing
electrodes, the ESD electrodes, the first bridges are disposed on
the substrate. The passivation layer is disposed between the
sensing electrodes and the first bridges, and the passivation layer
is also disposed between the ESD protection electrodes and the
first bridges. Besides, the passivation layer has a plurality of
contact holes, and at least one of the sensing electrodes is
electrically connected with the ESD protection electrode via the
contact holes and the first bridges.
According to the design of the ESD protection electrodes in the
present invention, the energy of the ESD damage, which may be
generated during the fabrication process or the operation of the
touch panel, may be released. The probability of damaging the
connecting lines may then be decreased, and the reliability of the
touch panel may be effectively improved. Besides, the manufacturing
method of the sensing structure of the touch panel in the present
invention may be integrated into the current process of the touch
panel, and therefore, no extra process is required. The cost and
the complexity of the manufacturing process of the touch panel may
not be increased.
These and other objectives of the present invention will no doubt
become obvious to those of ordinary skill in the art after reading
the following detailed description of the preferred embodiment that
is illustrated in the various figures and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic diagram illustrating a top view of the
conventional sensing structure of the touch panel.
FIGS. 2-4 are schematic diagrams illustrating the sensing structure
of the touch panel according to the first preferred embodiment of
the present invention.
FIG. 5 is a schematic diagram illustrating the equivalent circuits
of the sensing structure of the touch panel according to the
preferred embodiment of the present invention.
FIGS. 6-8 are schematic diagrams illustrating the sensing structure
of the touch panel according to the second preferred embodiment of
the present invention.
FIG. 9 is a schematic diagram illustrating a top view of the
sensing structure of the touch panel according to the third
preferred embodiment of the present invention.
FIGS. 10-12 are schematic diagrams illustrating the collocations of
the sensing structure of the touch panel and the display panel
according to the present invention.
DETAILED DESCRIPTION
Certain terms are used throughout the description and following
claims to refer to particular components. As one skilled in the art
will understand, electronic equipment manufacturers may refer to a
component by different names. This document does not intend to
distinguish between components that differ in name but not
function. In the following description and in the claims, the terms
"include" and "comprise" are used in an open-ended fashion, and
thus should be interpreted to mean "include, but not limited to . .
. " In addition, to simplify the descriptions and make it more
convenient to compare between each embodiment, identical components
are marked with the same reference numerals in each of the
following embodiments. Please note that the figures are only for
illustration and the figures may not be to scale. Additionally, the
terms such as "first" and "second" in this context are only used to
distinguish different components and do not constrain the order of
generation.
Please refer to FIGS. 2-4. FIGS. 2-4 are schematic diagrams
illustrating the sensing structure of the touch panel according to
a first preferred embodiment of the present invention. FIG. 2 is a
schematic diagram illustrating a top view of the sensing structure
of the touch panel. FIG. 3 is a perspective of a local enlargement
of FIG. 2. FIG. 4 is a schematic diagram illustrating a
cross-sectional view along a line A-A' in FIG. 3. As shown in FIGS.
2-4, the sensing structure 51 of the touch panel in the first
preferred embodiment of the present invention includes a substrate
10, a plurality of first bridges 11A disposed on the substrate 10,
a plurality of second bridges 11B disposed on the substrate 10, a
passivation layer 12 (not shown in FIG. 2 and FIG. 3) disposed on
the first bridges 11A and the second bridges 11B, a plurality of
sensing electrodes 14A/14B disposed on the passivation layer 12,
and a plurality of ESD protection electrodes 15 disposed on the
passivation layer 12. The sensing electrodes 14A are disposed
interlacedly with the sensing electrodes 14B. A pattern of each of
the sensing electrodes 14A is separated from the pattern of other
sensing electrodes 14A, and the patterns of the sensing electrodes
14B are connected in a horizontal direction X. Each of the ESD
protection electrodes 15 is disposed between each of the sensing
electrodes 14A and each of the sensing electrodes 14B. Each of the
patterns of the ESD protection electrodes 15 is separated from the
patterns of the sensing electrodes 14A and the sensing electrodes
14B. In addition, the passivation layer 12 has a plurality of
contact holes 13, and the contact holes 13 respectively expose a
part of the first bridges 11A and a part of the second bridges 11B.
At least one of the sensing electrodes 14A is electrically
connected with the ESD protection electrode 15 via the contact
holes 13 and the first bridges 11A, and at least one of the sensing
electrodes 14A is electrically connected with the adjacent sensing
electrode 14A in a vertical direction Y via the contact holes 13
and the second bridges 11B. In other embodiments of the present
invention, some of the ESD protection electrodes 15 may selectively
be electrically connected with the sensing electrodes 14B via the
first bridges 11A, according to different design purposes, but the
sensing electrodes 14A are still electrically disconnected with the
sensing electrodes 14B. In this embodiment, the first bridges 11A
and the second bridges 11B are formed by an identical conductive
material layer, and the conductive material layer may include such
as molybdenum (Mo), aluminum (Al), titanium (Ti) or other
appropriate conductive materials. The sensing electrodes 14A/14B
and the ESD protection electrodes 15 are formed by an identical
transparent conductive material layer, and the transparent
conductive material layer may include indium tin oxide (ITO),
indium zinc oxide (IZO), aluminum zinc oxide (AZO), or other
appropriate conductive materials. In other embodiments in the
present invention, the sensing electrodes and the ESD protection
electrodes may be formed by an opaque conductive material layer or
by a conductive material layer with low transmittance. For example,
appropriate opaque conductive materials or conductive materials
with low transmittance may be used to form the sensing electrodes
and the ESD protection electrodes to achieve other purposes, such
as lower cost, while the touch panel is not applied with the
display panel or there are no demands for high transmittance of the
whole panel. Please refer to FIG. 3. As shown in FIG. 3, each of
the first bridges 11A includes two contact parts 11A2 and one
connection part 11A1. A width W11 of the connection part 11A1 may
be substantially wider than or equal to a width W2 of the second
bridge 11B, and a width W12 of the contact part 11A2 may be
substantially wider than the width W11 of the connection part 11A1.
In the embodiments of the present invention, preferably, the width
W12 of the contact part 11A2 may be substantially equal to twice
the width W11 of the connection part 11A1, but the present
invention is not limited to this. According to the above-mentioned
design, the probability that the electric current passes through
the ESD protection electrodes 15 may be increased by controlling
the width of the first bridge 11A connected with the ESD protection
electrode 15. The ESD protection purpose may then be achieved,
because a heavy current generated by the ESD may tend to be led
toward the ESD protection electrode 15 via the bridge 11A. The
mechanism of the ESD protection in the present invention will be
detailed in the following content.
Please refer to FIG. 4, and refer to FIG. 3 together. According to
the first preferred embodiment of the present invention, a
manufacturing method of the sensing structure of the touch panel
includes the following steps. Firstly, a substrate 10 is provided.
A patterned conductive layer is formed on the substrate 10 for
forming a plurality of first bridges 11A and a plurality of second
bridges 11B. Each of the first bridges 11A includes two contact
parts 11A2 and a connection part 11A1. A width W11 of the
connection part 11A1 is substantially wider than or equal to a
width W2 of the second bridge 11B, and a width W12 of the contact
part 11A2 may be substantially wider than the width W11 of the
connection part 11A1. Subsequently, a passivation layer 12 is
formed to cover the substrate 10, the first bridges 11A, and the
second bridges 11B. Afterward, a plurality of contact holes 13 are
formed in the passivation layer 12. The contact holes 13
respectively expose a part of the first bridges 11A and a part of
the second bridges 11B. A patterned transparent conductive layer is
then formed on the passivation layer 12 for forming a plurality of
sensing electrodes 14A, a plurality of sensing electrodes 14B, and
a plurality of ESD protection electrodes 15. At least one of the
sensing electrodes 14A contacts a part of the first bridge 11A and
a part of the second bridge 11B via the contact holes 13, and at
least one of the ESD protection electrodes 15 contacts a part of
the first bridge 11A via the contact holes 13. In other words, at
least one of the sensing electrodes 14A is electrically connected
with the ESD protection electrode 15 via the contact holes 13 and
the first bridges 11A, and at least one of the sensing electrodes
14A is electrically connected with the adjacent sensing electrode
14A via the contact holes 13 and the second bridges 11B. It is
worth noticing that the manufacturing method of the sensing
structure of the touch panel in the present invention may be
integrated into the current process of the touch panel, and
therefore, no extra process is required. The cost and the
complexity of the manufacturing process may not be increased.
Please refer to FIG. 5, and refer to FIG. 2 together. FIG. 5 is a
schematic diagram illustrating the equivalent circuits of the
sensing structure of the touch panel according to the preferred
embodiment of the present invention. As shown in FIG. 5, in the
first preferred embodiment of the present invention, a resistance
R.sub.trace represents an equivalent resistance of each of the
second bridges 11B, which are connected to the sensing electrodes
14A. A resistance R.sub.esd represents an equivalent resistance of
each of the ESD protection electrodes 15 and the first bridges 11A,
which are connected to the ESD protection electrodes 15. A
resistance R.sub.ts represents an equivalent resistance of each of
the sensing electrodes 14A. A sudden heavy current I.sub.esd may go
through the second bridges 11B, which are connected to the sensing
electrodes 14A in the vertical direction Y, and then the path of
the heavy current I.sub.esd may be divided into three branches.
Because the resistance R.sub.esd is substantially larger than the
resistance R.sub.ts, a thermal energy generated by the heavy
current I.sub.esd may become larger at the ESD protection
electrodes, and the heavy current I.sub.esd may damage the ESD
protection electrodes more likely. Based on the design of the ESD
protection electrode in the present invention, the energy of the
ESD damage may be effectively scattered. The probability of
damaging the connecting lines (such as the second bridges 11B) may
then be decreased, and the reliability of the touch panel may be
effectively improved.
Please refer to FIGS. 6-8. FIGS. 6-8 are schematic diagrams
illustrating the sensing structure of the touch panel according to
a second preferred embodiment of the present invention. FIG. 6 is a
schematic diagram illustrating a top view of the sensing structure
of the touch panel. FIG. 7 is a perspective of a local enlargement
of FIG. 6. FIG. 8 is a schematic diagram illustrating a
cross-sectional view along the line A-A' in FIG. 7. In this
embodiment, each of the components and the material properties of
the sensing structure of the touch panel are identical with those
in the first preferred embodiment mentioned above. For
simplification, each of the identical components is marked with the
same symbol in the first and the second preferred embodiments. As
shown in FIGS. 6-8, the sensing structure 52 of the touch panel in
the second preferred embodiment of the present invention includes a
substrate 10, a plurality of sensing electrodes 14A/14B disposed on
the substrate 10, a plurality of ESD protection electrodes 15
disposed on the substrate 10, a passivation layer 12 disposed on
the sensing electrodes 14A/14B and the ESD protection electrodes
15, a plurality of first bridges 11A and second bridges 11B
disposed on the passivation layer 12. The sensing electrodes 14A
are disposed interlacedly with the sensing electrodes 14B, a
pattern of each of the sensing electrodes 14A is separated from the
pattern of other sensing electrodes 14A, and the patterns of the
sensing electrodes 14B are connected in a horizontal direction X.
Each of the ESD protection electrodes 15 is disposed between each
of the sensing electrodes 14A and each of the sensing electrodes
14B. Each of the patterns of the ESD protection electrodes 15 is
separated from the patterns of the sensing electrodes 14A and the
sensing electrodes 14B. Additionally, the passivation layer 12 has
a plurality of contact holes 13, and the contact holes 13
respectively expose a part of the sensing electrodes 14A and a part
of the ESD protection electrodes 15. At least one of the sensing
electrodes 14A is electrically connected with the ESD protection
electrode 15 via the contact holes 13 and the first bridges 11A,
and at least one of the sensing electrodes 14A is electrically
connected with the adjacent sensing electrode 14A in a vertical
direction Y via the contact holes 13 and the second bridges 11B.
Please refer to FIG. 7. As shown in FIG. 7, each of the first
bridges 11A includes two contact parts 11A2 and one connection part
11A1. A width W11 of the connection part 11A1 may be substantially
wider than or equal to a width W2 of the second bridge 11B, and a
width W12 of the contact part 11A2 may be substantially wider than
the width W11 of the connection part 11A1. Preferably, the width
W12 of the contact part 11A2 may be substantially equal to twice
the width W11 of the connection part 11A1, but the present
invention is not limited to this.
Please refer to FIG. 8, and refer to FIG. 7 together. According to
the second preferred embodiment of the present invention, a
manufacturing method of the sensing structure of the touch panel
includes the following steps. Firstly, a substrate 10 is provided.
A patterned transparent conductive layer is formed on the substrate
10 for forming a plurality of sensing electrodes 14A, a plurality
of sensing electrodes 14B, and a plurality of ESD protection
electrodes 15. Subsequently, a passivation layer 12 is formed to
cover the substrate 10, the sensing electrodes 14A, the sensing
electrodes 14B, and the ESD protection electrodes 15. Afterward, a
plurality of contact holes 13 are formed in the passivation layer
12. The contact holes 13 respectively expose a part of the sensing
electrodes 14A and a part of the ESD protection electrodes 15. A
patterned conductive layer is then formed on the passivation layer
12 for forming a plurality of first bridges 11A and a plurality of
second bridges 11B. Each of the first bridges 11A includes two
contact parts 11A2 and a connection part 11A1. A width W11 of the
connection part 11A1 is substantially wider than or equal to a
width W2 of the second bridge 11B, and a width W12 of the contact
part 11A2 may be substantially wider than the width W11 of the
connection part 11A1. At least one of the sensing electrodes 14A
contacts a part of the first bridge 11A and a part of the second
bridge 11B via the contact holes 13, and at least one of the ESD
protection electrodes 15 contacts a part of the first bridge 11A
via the contact holes 13. In other words, at least one of the
sensing electrodes 14A is electrically connected with the ESD
protection electrode 15 via the contact holes 13 and the first
bridges 11A, and at least one of the sensing electrodes 14A is
electrically connected with the adjacent sensing electrode 14A via
the contact holes 13 and the second bridges 11B.
Please refer to FIG. 9. FIG. 9 is a schematic diagram illustrating
a top view of the sensing structure of the touch panel according to
the third preferred embodiment of the present invention. To
simplify the description, only one sensing electrode and the
collocated ESD protection electrodes are illustrated in FIG. 9. The
following description will detail the dissimilarities among
different embodiments and the identical components will not be
redundantly described. In addition, some of the components and the
material properties of the sensing structure of the touch panel in
this embodiment are identical to those in the first embodiment. To
simplify the description, the identical components are labeled with
the same mark. As shown in FIG. 9, in this embodiment, the sensing
electrode 14A is a pattern of a rhombus with a hollow region 17,
but the sensing electrode 14A in the present invention is not
limited to this and may be other appropriate patterns with a hollow
region. An ESD protection electrode 16 is disposed in the hollow
region 17, and the pattern of the ESD protection electrode is
separated from the pattern of the sensing electrode 14A. Each of
the first bridges 11A includes two contact parts 11A2 and a
connection part 11A1. A width W11 of the connection part 11A1 is
substantially wider than or equal to a width W2 of the second
bridge 11B, and a width W12 of the contact part 11A2 may be
substantially wider than the width W11 of the connection part 11A1.
At least one of the sensing electrodes 14A is electrically
connected with the ESD protection electrode 16 via the contact
holes 13 and the first bridges 11A, and at least one of the sensing
electrodes 14A is electrically connected with the adjacent sensing
electrode 14A via the contact holes 13 and the second bridges 11B.
In other embodiments of the present invention, for better ESD
protection effect, some of the sensing electrodes 14A and the
sensing electrodes 14B may selectively be electrically connected
with the ESD protection electrodes 16 inside the patterns of the
sensing electrodes 14A/14B, or be electrically connected with the
ESD protection electrodes 15 outside the sensing electrodes
14A/14B. The manufacturing method of the sensing structure of the
touch panel in this embodiment may be identical to the
manufacturing methods described in the first preferred embodiment
and the second preferred embodiment. In other words, according to
different design purposes, the first bridges 11A and the second
bridges 11B may be disposed over the sensing electrodes 14A/14B or
may be disposed under the sensing electrodes 14A/14B in this
embodiment. The details of the manufacturing method of this
embodiment are identical to those of the above described
embodiments, and will not be redundantly described.
The equivalent circuits of the sensing structure of the touch panel
according to the third preferred embodiment of the present
invention may be represented by FIG. 5. Please refer to FIG. 5
again, and refer to FIG. 9 together. As shown in FIG. 5, a
resistance R.sub.esd represents an equivalent resistance of each of
the ESD protection electrodes 16 and the first bridges 11A, which
are connected to the ESD protection electrodes 16. A resistance
R.sub.trace represents an equivalent resistance of each of the
second bridges 11B. A resistance R.sub.ts represents an equivalent
resistance of each of the sensing electrodes 14A. A sudden heavy
current I.sub.esd may go through the second bridges 11B, which are
connected to the sensing electrodes 14A in the vertical direction
Y. Because the resistance R.sub.esd is substantially larger than
the resistance R.sub.ts, a thermal energy generated by the heavy
current I.sub.esd may become larger at the ESD protection
electrodes, and the heavy current I.sub.esd may damage the ESD
protection electrodes more likely. Based on the design of the ESD
protection electrode in this embodiment, the energy of the ESD
damage may be effectively scattered. The probability of damaging
the connecting lines (such as the second bridges 11B) may then be
decreased, and the reliability of the touch panel may be
effectively improved.
Please refer to FIGS. 10-12. FIGS. 10-12 are schematic diagrams
illustrating the collocations of the sensing structure of the touch
panel and the display panel according to the present invention. As
shown in FIGS. 10-12, a display panel 30 includes a substrate 31, a
substrate 32, and a display medium layer 33. The substrate 31
includes an inner surface 311 and an outer surface 312. The
substrate 32 includes an inner surface 321 and an outer surface
322. The substrate 31 is disposed oppositely and parallel to the
substrate 32. The inner surface 311 of the substrate 31 faces the
inner surface 321 of the substrate 32. The display medium layer 33
is disposed between the substrate 31 and the substrate 32. To
simplify the description, the sensing electrodes 14A/14B, the ESD
protection electrodes 15/16, the first bridge 11A, the second
bridge 11B and the passivation layer 12 in the above-mentioned
embodiments are totally represented by a sensing device layer 40.
As shown in FIG. 10, the substrate 10 in the above-mentioned
embodiments may be the substrate 32 of the display panel 30. In
other words, the sensing device layer 40 may be disposed on the
outer surface 322 of the substrate 32 as an on-cell touch panel.
Besides, as shown in FIG. 11, the sensing device layer 40 may be
disposed on the inner surface 321 of the substrate 32 as an in-cell
touch panel. Additionally, as shown in FIG. 12, the substrate 10 in
the above-mentioned embodiments may be disposed on the outer
surface 322 of the substrate 32 as an out-cell touch panel. In the
present invention, the display panel 30 may be a liquid crystal
display panel, and the substrate 32 may be a color filter
substrate, a transparent substrate, or other appropriate substrate.
The display panel 30 in the resent invention is not limited to the
liquid crystal display panel and may be other kinds of the display
devices.
To summarize all the descriptions above, the energy of the ESD
damage, which may be generated during the fabrication process or
the operation of the touch panel, may be released by the design of
the ESD protection electrodes in the present invention. The
probability of damaging the connecting lines may then be decreased,
and the reliability of the touch panel may be effectively improved.
Besides, the manufacturing method of the sensing structure of the
touch panel in the present invention may be integrated into the
current process of the touch panel, and therefore, no extra process
is required, and the cost and the complexity of the manufacturing
process may not be increased.
Those skilled in the art will readily observe that numerous
modifications and alterations of the device and method may be made
while retaining the teachings of the invention.
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